Prosthetic having a modular soft tissue fixation mechanism

ABSTRACT

A method and apparatus for coupling soft tissue to a prosthetic is disclosed. Soft tissue attachment pads having porous metal attachment regions and suture accepting holes are selectively positioned onto an implantable prosthetic to provide coupling locations.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. patent application Ser. No.13/085,538 filed on Apr. 13, 2011, which claims the benefit of U.S.Provisional Application No. 61/323,666, filed on Apr. 13, 2010. Theentire disclosure of each of the above applications is incorporatedherein by reference in its entirety.

FIELD

This invention relates generally to a method and apparatus for use inorthopedic surgery and, more particularly, to a method and apparatus forproviding a prosthesis having a modular soft tissue coupling mechanism.The soft tissue coupling mechanism is a member configured to beoptionally and selectively coupled to the implant and includes afixation flange and porous metal portion, both of which are configuredof being coupled to soft tissues.

BACKGROUND

It is generally known in the art to provide prostheses that replace orreinforce various portions of bone during an orthopedic surgicalprocedure. However, the current prior art prostheses along with theassociated surgical components and instruments utilized duringorthopedic surgery may suffer from many disadvantages.

For example, because the extent of degradation is not always evidentuntil during the surgery, extensive bone resection may be necessary.Additionally, etiologies such as bone tumors or those requiring revisionof an implanted joint require significant bone removal which may removesoft tissue fixation sites. In these cases, soft tissue fixation to theprosthesis may or may not be necessary. To provide for soft tissueattachment, some replacement joint components provide an integral flangeconfigured to accept soft tissue attached to a lateral surface of theprosthetic replacement joint head. These fixed fixation flanges,however, may not provide the proper locational adaptivity needed duringthe orthopedic surgical procedure and leave the surgeon with littleflexibility or no options as to soft tissue attachment.

An example of an orthopedic transplant is a shoulder prosthesis whichtypically comprises a humeral component and a glenoid component. Thehumeral component and the glenoid component are designed to besurgically attached to the distal end of the humerus and the scapula,respectively. The humeral component is further designed to cooperatewith the scapula component in simulating the articulating motion of ananatomical shoulder joint.

Motion of a natural shoulder is kinematically complex. During arelatively broad range of flexion and extension, the articular orbearing surfaces of a natural shoulder experience rotation, medial andlateral angulation, translation, rollback and sliding. Shoulder jointprostheses, in combination with ligaments and muscles, attempt toduplicate this natural shoulder motion, as well as absorb and controlforces generated during the range of motion. Depending on the degree ofdamage or deterioration of the shoulder tendons and ligaments, however,it may be necessary for a shoulder joint prosthesis to eliminate one ormore of these motions in order to provide adequate stability.

What is needed then is a prosthesis and associated surgical componentsfor use in orthopedic surgery which does not suffer from theabove-mentioned disadvantages. This in turn, will provide a prosthesiswhich is stable and secure and increases the overall flexibility for asurgeon to fix soft tissues. It is, therefore, an object of the presentinvention to provide such a prosthesis and associated surgicalcomponents for use in orthopedic surgery.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

In accordance with the present teachings, an apparatus and method forproviding a prosthetic having a modular soft tissue attachment mechanismis disclosed. The apparatus and method employ modular soft tissueattachment mechanisms having porous metal pads for use during theorthopedic surgical procedure.

In one embodiment, an orthopedic implant has a body that is at leastpartially implantable within a bone. A mechanism for coupling softtissue to the body is provided. The mechanism for coupling soft tissueto the body has an attachment member operable to prevent movement of thecoupling mechanism with respect to the body. The mechanism defines asuture accepting aperture configured to couple soft tissue to themechanism and has a porous soft tissue engaging surface.

A method for implanting a shoulder prosthetic is further disclosed. Themethod includes selecting an appropriately sized prosthetic component.Next, a determination is made if soft tissue fixation to the implant isnecessary. Should it be necessary to couple soft tissue to the implant,a soft tissue fixation having a porous metal component is attached tothe implant. The implant is subsequently implanted. Soft tissue ispositioned adjacent to the porous metal component and allowed to growinto the porous metal component.

Use of the present teachings provides an apparatus and method forproviding a prosthetic having a modular soft tissue attachment mechanismfor use during an orthopedic surgical procedure. As a result, theaforementioned disadvantages associated with the currently availableprostheses and associated surgical components have been substantiallyreduced or eliminated.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIGS. 1A and 1B are an assembled view of the prosthetic componentaccording to the teachings of one embodiment;

FIG. 2 is a side view of an alternate base humeral component withhumeral head according to the present teachings;

FIG. 3 represents an alternate view of the humeral component shown inFIG. 2 according to the present teachings;

FIG. 4 represents a soft tissue fixation member coupled to the humeralcomponent of the present teachings;

FIGS. 5-7 represent perspective, side and rear views of a prostheticaccording to the present teachings;

FIGS. 8A-8C represent the top, end and side views of a soft tissuefixation member according to the present teachings;

FIG. 9 represents a sectional view of the soft tissue coupling member ofFIGS. 8A-8C;

FIGS. 10A and 10B represent soft tissue coupling mechanisms according tothe present teachings;

FIG. 11 represents a perspective view of the soft tissue couplingmechanism without the porous coupling member;

FIG. 12 represents a side view of the soft tissue coupling member ofFIG. 10B;

FIG. 13 represents the coupling of the soft tissue coupling mechanism toa prosthetic stem;

FIG. 14 represents a subassembly of soft tissue coupling mechanismscoupled to a head fixation member;

FIG. 15 represents the coupling of soft tissue coupling members to afemoral component;

FIG. 16 represents an alternate soft tissue coupling member;

FIG. 17 represents an exploded view of the soft tissue coupling memberbeing fixed to a coupling surface on a prosthetic;

FIGS. 18A and 18B represent the coupling of the soft tissue couplingmember according to FIG. 16 to a femoral prosthetic;

FIG. 19 represents an implanted view of the soft tissue coupling memberaccording to FIG. 16 coupled to a humeral prosthetic;

FIG. 20 represents the use of the soft tissue coupling member on afemoral prosthetic;

FIG. 21 represent a cross-sectional view of the soft tissue couplingmember coupled to the humeral stem of FIG. 19; and

FIGS. 22 and 23 represent femoral head coupling members having softtissue coupling mechanisms according to the present teachings.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings. FIGS. 1A and 1B represent components used ina shoulder arthroplasty according to the present teachings. As shown, amodular humeral component 31 has a base member 32, and a head member 33having an articulating bearing surface. Optionally, the modular humeralcomponent 31 can have a fixation stem 34 (see FIG. 1A) or an elbowprosthesis 35 (see FIG. 1B).

The base member 32 is configured to be coupled to the fixation stem 34and head 33 using coupling tapers (not shown). The fixation stem 34 canbe used to attach the modular humeral component 31 to a resected bone ofthe humerus.

If a total humeral replacement is being conducted, the modular humeralcomponent 31 shown in FIG. 1B can be used. The elbow prosthesis 35 canbe coupled to a fixation stem 34 using locking tapers or other suitablecoupling mechanism.

Attached to the modular humeral component 31 is a plurality of modularsoft tissue attachment pads 37. The soft tissue attachment pads 37 havea coupling surface 38 which is configured to be selectively coupled to acoupling surface 39 on the modular humeral component 31. In this regard,the modular humeral component 31 has a plurality of apertures 40 definedat various locations on the surface of the modular humeral component 31therein. The apertures 40 are configured to accept coupling fastenerswhich are configured to couple the soft tissue attachment pads 37 tospecific locations on the modular humeral component 31.

The soft tissue attachment pads 37 function as soft tissue couplinglocations. In this regard, the soft tissue attachment pads 37 define abore 43 configured to accept a suture engaged with soft tissue such as atendon, ligament or muscle. In practice, after the modular humeralcomponent 31 is coupled to the patient, soft tissue is coupled to thesoft tissue attachment pads 37 by passing the suture through the softtissue and passing the suture through the bore 43. The soft tissue canthen be positioned so that the soft tissue is in contact with a porousmetal surface. The soft tissue then grows into the porous metal surface,aiding in fixation.

FIGS. 2-4 represent the base member 32 having associated soft tissueattachment pads 37. As shown in FIG. 3, soft tissue attachment pads 37define a fastener accepting through bore 41. The through bore 41 isconfigured to be aligned with a bore 40 defined in the base member 32.

FIGS. 5-7 represent perspective, rear and front views of the base member32. Defined in the base member 32 are coupling tapers 50 which are usedto couple the base portion to the head or the fixation stem. Alsodefined in the base member 32 is a plurality of threaded fasteneraccepting bores 41. These fastener accepting bores 41 can be generallylocated at soft tissue accepting locations. It is, of course, envisionedthat a physician may need to fix soft tissue to non-traditionallocations due to damage to the soft tissue.

FIGS. 8A through 8C represent top, end and side views of the soft tissueattachment mechanism. The soft tissue attachment pads 37 have a plate 52made of a biocompatible material such as titanium. Disposed on the plateis a pad of porous metal material 53 such as Regenerex. Defined throughthe porous metal pad 56 and plate 52 is the fastener accepting aperture.

As best seen in FIG. 8C, disposed on proximal and distal ends are a pairof flanges 54 which define suture accepting bores 43. In use, a sutureis passed through soft tissue and then passed through the sutureaccepting bore 43 of the pair of flanges 54. The suture accepting bores43 are shown as being generally parallel to the center of curvature “C”of the coupling surface 38 of the soft tissue attachment pads 37. Asdescribed below, the suture accepting bores can be parallel to, skew orperpendicular to the coupling surface 38.

FIG. 9 represents a cross-sectional view of the soft tissue attachmentpads 37. Shown is the plate 52 having the coupling surface 38 configuredto mate against an implant or bone. Also shown is the porous metal pad56 which functions as a site for ingrowth of the soft tissue.

FIGS. 10A and 10B represent alternate soft tissue attachment pads 37. Asshown, the plate 52 can have varying axial lengths. Additionally shownis an alternate configuration for the suture accepting bores 43. Thefastener accepting bore 41 can be angularly adjusted in a non-centeredmanner from one of the terminal end 45 of the soft tissue attachment pad37. The suture accepting bores 43 are aligned so that at least a portionof the bore is disposed on a terminal end 45 of the soft tissueattachment pad 37 or plate 52. This allows the treating physician tocouple the soft tissue attachment pad 37 to the prosthetic after thecoupling thereto.

FIG. 11 represents the plate 52 for the soft tissue attachment pad 37.Shown is a notched surface 47 which is configured to accept the porousmetal pad 56. Optionally, the notched surface 47 has a pair of terminaledges 49 which can define the depth of the porous metal pad 56. Porousmetal pad 56 is a separate member which can be made of porous metal,porous coated metal or some biologic material. The porous metal pad 56can be attached to plate 52 by cement, glue, weld, sintering, etc.Alternatively, the area defined by notched surface 47 can be filled withporous plasma spray. The metal pad 56 can have a porosity of about 70%and a pore size ranging from about 300-600 microns. This pore size canimprove function in vivo. The open pores allowvascularization/angiogenesis and nutrient delivery which can beimportant for soft tissue in-growth or insertion. Traditional plasmaspray is not thought to provide these benefits.

FIG. 12 represents a side view of the plate 52 shown in FIG. 11. Shownin the plate 52 is the defined fastener accepting bore 41. The bore 41has a first portion with a generally cylindrical cross-section.Optionally, a fastener bearing surface 48 can be defined in a secondportion of the bore 41. Also shown is a cross-section of the sutureaccepting bore 43. The suture accepting bore 43 has a curved surface 55which is configured to reduce the risk of breakage of the suture. Thebores 43 are positioned in a way which located one end of the bore 43 onan exterior curved surface of the soft tissue attachment pad 37. Theother end of the bore can be formed in the terminal ends 45 of the softtissue attachment pads 37.

As shown in FIGS. 13-15, the soft tissue attachment pads 37 according toFIGS. 8A-12 can be coupled to various locations on disparate portions ofmonolithic or modular prosthetic systems depending upon the need of thetreating physician. The soft tissue attachment pads 37 can have varyingthicknesses of axial length depending upon the need of the patient.

FIGS. 16-21 represent an alternate soft tissue attachment pad 37. Thesoft tissue attachment pads 37 can have a generally planar yet circularconfiguration. A central portion 60 of the soft tissue attachment pads37 can support the porous metal pad 56. Disposed about the periphery 64of the soft tissue attachment pads 37 is a rim 66 defining the pluralityof suture accepting bore 43. As shown in FIG. 17, the soft tissueattachment pad 37 has a planar coupling surface 38 which can be coupledto a curved intermediate member 68. The curved intermediate member 68has a planar bearing or coupling surface 39 which mates with the planarcoupling surface 38 on the soft tissue attachment pad 37. The curvedintermediate member 68 has a curved surface configured to couple to acurved surface on the prosthetic.

As shown in FIGS. 18A and 18B, the soft tissue attachment pad 37 can becoupled either to a planar or a curved surface. By rotation of the softtissue attachment pad 37 about the fastener accepting bore 41, thelocation of the suture accepting bores 43 can be adjusted. By offsettingthe bore 41, rotation of the soft tissue attachment pad 37 willtranslate the location of the suture accepting bores 43 with respect tothe prosthetic.

FIGS. 19 and 20 represent implanted prosthetics 70 and 90 according tothe present teachings. As shown, both the soft tissue attachment padsaccording to FIGS. 1-10A and FIGS. 6 and 7 can be used with the sameimplant. FIG. 19 represents a humeral prosthetic 70 having a humeralfixation stem 72, an intermediate portion 74, a head coupling portion76, and head 33. As is known, the portions of the implant can be coupledtogether using locking tapers 78. The use of the soft tissue attachmentpads 76 allows for a treating physician to selectively attach softtissue to various locations on the prosthetic 70. Optionally, ininstances where the soft tissue is not an appropriate length due todegradation, the soft tissue can be coupled to the prosthetic at alocation which does not represent the normal location of soft tissueattachment to the bone. Multiple sutures 86 can be used to hold softtissue at a location adjacent to the porous metal portion of the softtissue attachment pad 37. Optionally, the loops of sutures 88 can bearranged to couple the soft tissue 84 to the prosthetic 70.

FIG. 20 represents a femoral prosthetic 90 with associated soft tissuecoupling pads according to the present teachings. Shown is the couplingof pads having both planar and curved coupling surfaces 38. Afterimplantation of the prosthetic 90 into the resected femur 94, the softtissue associated with the patella 96 can be coupled to the prosthetic90. Depending on the amount of damage, the soft tissue 98 can be placedin direct contact with the soft tissue attachment pad 37 or can bedisassociated and coupled with suture loops 88 or artificial graftmaterial.

As briefly described above and shown in FIG. 21, the soft tissueattachment pads 37 can be rotatably positioned about an axis 100generally disposed along the axis of the coupling bore 41. Afterimplantation of the prosthetic 70, a treating physician can couple thesoft tissue attachment pad 37 to the prosthetic 70 using a couplingmechanism such as a threaded fastener. It is envisioned the soft tissueattachment pads 37 can also be attached using other mechanism such as alocking taper, deformable flanges or translatable members.

FIGS. 22 and 23 represent alternate components 102 and 104 of aprosthetic. These intermediate femoral members are shown to illustratesome of the various surfaces which can be utilized to couple the softtissue attachment pads 37 to the prosthetic. In this regard, it isenvisioned the soft tissue attachment pads 37 can be configured to becoupled to convex rail features 110 (see FIG. 1B), planar features (seeFIG. 21) or concave channel features 112 (see FIG. 22). The variety ofcoupling surfaces 38, 39 and locations is intended to give the treatingphysician maximum flexibility in the operating theater.

While the soft tissue attachment pad 37 is shown throughout theapplication as a cylindrical surface disposed on an implant positionedwithin an intermedullary canal, it should be noted that the soft tissuefixation members can further take the form of a plate coupled to eithera cylindrical or flat baseplate member. In this regard, the soft tissuefixation mechanisms can take the form of a plate member capable ofaccepting a suture or suture anchor. Additionally, the prosthetic neednot be associated with a joint, e.g. an intercalary member.

Additionally, the soft tissue fixation mechanisms can be adjustablypositioned on the prosthetic in one or more fixation areas. In thisregard, multiple soft tissue fixation mechanisms can be located onmultiple locations of a single implant. While the soft tissue fixationmechanisms is shown on a modular prosthetic, those skilled in the artwill recognize that only the soft tissue fixation mechanisms need bemodular and that the soft tissue fixation mechanisms can be fixed to anysingle piece prosthetic device. It is envisioned that a kit can beformed utilizing various sized prosthetic as well as various types andsizes of soft tissue coupling mechanisms.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

The description of the invention is merely exemplary embodiments in thepresent invention. One skilled in the art would readily recognize fromsuch discussion and from accompanying drawings and claims that variouschanges, modifications, variations may be made therein without thespirit and scope of the invention. For example, while the soft tissuefixation mechanisms are shown being coupled to a humeral, femoral, ortibial implant, the soft tissue fixation mechanism can equally beapplied to other joint implants such as, but not limited to, knees andelbows, and for whole bone replacement.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the invention. Individual elements or features ofa particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the invention, and all such modificationsare intended to be included within the scope of the invention.

What is claimed is:
 1. An orthopedic implant comprising: an implanthaving an articulating surface and a bone attachment region forming acomplete functional implant configured to be implanted into a patient;and a soft tissue attachment pad having a porous coating on a softtissue engaging surface, said soft tissue attachment pad operable to beattached to said implant with a locking mechanism, wherein said lockingmechanism is configured to prevent movement of the soft tissueattachment pad with respect to the implant and wherein said completeimplant is configured to be implanted into the bone in a firstfunctional configuration with the soft tissue attachment pad and in asecond functional configuration without the soft tissue attachment pad.2. The orthopedic implant according to claim 1 wherein the lockingmechanism is set off with respect to a center line of the soft tissueattachment pad to allow selective positioning of the soft tissueattachment pad with respect to the implant.
 3. The orthopedic implantaccording to claim 1 wherein the soft tissue attachment pad comprises aflange defining a suture accepting bore therethrough.
 4. The orthopedicimplant according to claim 3 wherein the flange defines a plurality ofsuture bores.
 5. The orthopedic implant according to claim 3 whereinsaid bone attachment region is an exterior cylindrical surface whichdefines an axis, said suture accepting bore being parallel to the axis.6. The orthopedic implant according to claim 1 wherein the soft tissueattachment pad has a plate defining a suture accepting bore and a porousmetal pad disposed on the plate.
 7. A prosthetic comprising: a headportion having an articulating surface; a base member having a boneengaging surface defining a taper, said bone engaging surface coupleddirectly to said head portion to form a complete implantable prosthetic,said base member defining an outer fixation surface, said base memberhaving a locking mechanism; and a selectable attachable soft tissueattachment pad having a porous metal soft tissue fixation pad anddefining a suture accepting bore, said attachable soft tissue attachmentpad having a coupling mechanism, wherein said coupling mechanismfunctions to couple the soft tissue attachment pad to the outer fixationsurface, wherein said locking mechanism is configured to preventmovement of the soft tissue attachment pad with respect to the basemember.
 8. The prosthetic according to claim 7 wherein said lockingmechanism is a threaded fastener.
 9. The prosthetic according to claim 7wherein the soft tissue attachment pad comprises a generally planarplate having a planar fixation coupling surface.
 10. The prostheticaccording to claim 9 wherein the planar fixation coupling surface isconfigured to be coupled to a planar surface on the base member.
 11. Theprosthetic according to claim 9 further comprising an intermediarymember, said intermediary member defining a fastener accepting aperturetherethrough, and having an intermediary member planar bearing surfaceconfigured to interface with the planar fixation surface and anintermediary member curved bearing surface configured to interface witha base member convex surface.
 12. The prosthetic according to claim 9wherein a planar fixation coupling surface defines a fastener acceptingbore.
 13. The prosthetic according to claim 9 wherein the general planarplate is circular.
 14. The prosthetic according to claim 13 wherein theplate defines a central portion having the porous metal soft tissueattachment pad.
 15. The prosthetic according to claim 14 wherein theplate defines a circular rim.
 16. The prosthetic according to claim 15wherein the circular rim defines a plurality of suture accepting bores.17. The prosthetic according to claim 7 comprising a plurality oflocking mechanisms disposed on the outer fixation surface.
 18. A methodfor implanting an orthopedic prosthetic comprising: selecting anappropriately sized prosthetic; determining if soft tissue fixation tothe prosthetic is necessary; attaching a soft tissue attachment padhaving a porous metal portion to the prosthetic; implanting saidprosthetic; and coupling soft tissue to the porous metal portion. 19.The method for implanting an orthopedic device according to claim 18wherein attaching said soft tissue attachment pad to said prostheticincludes coupling said soft tissue attachment pad to an exterior surfaceof the prosthetic.
 20. The method according to claim 18 furthercomprising passing a suture through the soft tissue and passing thesuture through an aperture defined in the soft tissue attachment pad.